Electric wire connectors



A. L. VOGEL Jan. 28, 1964 IC WIRE CONNECTORS United States Patent 3,119,896 ELECTRIC WERE CONNECTORS Arthur L. Vogel, 56 Faint-U-Weods Drive, Toms River, lhl qlfiteiia M. Vogel, administratrix of said Arthur L.

g Fiied Sept. 11, 1962, Ser. No. 222,889

2 Qlairns. (Cl. 174-87) This invention relates to connectors for electric wires of the type wherein an insulating cap is utilized to twist together the ends of the wires to assure a good electrical connection between them and also to provide a cover and insulation for the twisted wires.

Heretofore there have been many proposed structures for twisting together a plurality of conductors, a common arrangement being the provision of a spring of generally conical shape disposed within a conical opening of an insulating cap. However, such caps can become dislodged thus to defeat the purpose of the insulation provided by the cap utilized to twist the wires together.

It has also been proposed that such springs have some of their turns disposed within threads formed along the conical opening and in some instances the turns at the small end of the spring are more widely spaced than the other turns, the purpose being to provide a better interlock between the spring and the conductors. Such an arrangement depends upon a fairly high degree of precision in dimensioning as between the connector itself and the twisted wires which obviously will vary in size depending upon the degree of twist, the diameter of the wires, and the skill of the operator. in many instances the cap is not retained on the wires but can be dislodged with likelihood of short circuits.

In carrying out the present invention in one form thereof, there is provided within a central longitudinal cavity of an insulating cap a free-floating spring of conical shape held at its base or large end by the disposition of the single turn of greatest diameter within a circular groove designed closely to fit and partially to encircle the enlarged turn of the spring. At the large end, the end of the spring extends radially into a recess or hole in the cap to prevent relative turning between the spring and the cap or shell. Free space is provided between the closed end of the cap or shell and the small end of the free-floating spring. This spring provides for the extension of conductors through the spaced turns of the spring and into the aforesaid free space. Clearance and free space are also provided between the conically shaped spring and the cavity of the cap in which it is disposed. In this manner the spring, by reason of its free-floating mount, adapts itself into alignment with conductors pushed into it at various angles. Upon turning the cap, the spring is wound about the conductors and in some instances, as braided conductors are twisted together the small strands are forced into and between the turns. The ends of the conductors are frequently pushed through the spring and form a pinched or enlarged end in the space provided therefor. The result is the completion of an electrical connection between one or more conductors inserted into a cap of low resistance since the conductors are tightly held together. The insulating cap is locked to the conductors since the spring is anchored to the cap. Any effort to pull the cap from the conductors collapses the spring; i.e., pulls the turns into closer relationship one with the other. This locking action increases as the pull on the cap is increased. The cap is securely held in place.

For a more complete description of the invention and for illustrations of several modifications thereof, reference is to be had to the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a sectional elevation of an embodiment of the invention;

"ice

FIG. 2 is a side elevation of the free-floating spring;

FIG. 3 is a sectional view taken on the line 3-3 of FIG. 1; and

FIG. 4 is a sectional view of a modification.

Referring now to the drawing, the electrical wire connector for bared ends of insulated conductors comprises an insulating cap ltl having a closed end 10a and an open end 101). Though the central longitudinal cavity has been illustrated as slightly conical in shape, it may be cylindrical. The cap 10 has near the open end 1012 a groove We designed to receive in close fitting relationship therewith a large-diameter turn 11a of a conically shaped spring 11. This large-diameter turn 11a is preferably the last turn of the spring and it has an end 1112 extending generally radially of the spring and is received within a closely fitting groove or cavity formed along an axial portion of the housing it The diameter of the turn 11a preferably is slightly larger than the groove ltig to insure a spring bias of the turn 11a into the recess.

It will be observed that the spring 11 has an axial length from the groove Mic to the closed inner wall of the cap it), less than that of the cavity to provide free space 159s at the end of the cavity. The cavity is larger than the spring 11 throughout its length to provide free space therebetween. Thus the spring 11 is free-floating and cantilever-supported within the longitudinal cavity by reason of the encirclement of the turn He by groove The and the spring-bias of the turn into the groove. The groove and the spring and cap may not be rotated relative to each other by reason of the driving connection or mechanical interlock between them provided by the end 11b of the spring disposed within the groove 10g of the cap. This groove is axially extending and is preferably narrow to receive the end 11b.

By reason of the foregoing structural features of the invention, braided or multiple strand conductors as frequently used in domestic wiring applications may simply have the bared ends inserted within the spring and the cap turned in a direction in which the spring acts as a tightening thread. The spring ill turns and twists the conductors with many of the smaller conductors protruding into and between the space between the turns of the spring.

in the preferred form of the invention, the spacing between adjacent turns of the spring may be from onefourth to one full diameter of the diameter of the spring wire. The turns are preferably uniformly spaced one from the other. The spring may be wound into a conical spiral with one end terminating at one end of the spring and the other end terminating at the outward extension 1111 as above described.

For solid conductors, they will in general be partly twisted together before application of the connector and thereafter the connector will be screwed onto the bared and twisted ends. By reason of the free-floating action of the spring, with uniform spacing between its turns and its conical shape it will not only apply spring pressure about the twisted ends to better the electrical contact but it will also form an interlock therewith safely to provide an insulating cap which may not be withdrawn even by the application of heavy withdrawal forces applied to the cap. The shortening of the space between the coils increases the gripping action and thus makes relatively impossible the removal of the cap in any manner except by unthreading it.

In summary, it is emphasized that this invention is principally based upon the provision of the conical spring within a cavity larger than the spring and with provision for the free-fioating mounting of the spring from its enlarged end and its interlocking with the cap to prevent relative rotation between the spring and cap. Thus in rotation of the cap 1% the free-floating spring within the cavity will be driven and threaded onto the conductors. Though the turns be closely spaced and less than the above minimum of one-quarter diameter of the spring wire, there will still be retained many advantages of the present invention. The spring may be wound either in right-hand or left-hand direction though in general it will be wound in a right-hand direction so that as the cap is twisted clockwise the spring will tighten its grip about the conductor.

Those skilled in the art will understand that the electrio-wire connectors of the present invention may be made in different sizes to accommodate wires of different sizes. Modifications may be made as shown in FIG. 4 where a radial hole 1911 is provided for the end 11b of the spring 11 instead of the slot of FIGS. 1 and 3.

What is claimed is:

1. An electrical wire connector for bared ends of insulated conductors comprising an insulating cap having a central longitudinal cavity therein open at the forward end and closed at the rear end with a groove adjacent said open end,

a freeloating spring of generally conical shape with the turns uniformly spaced one from the other and with its turn of maximum diameter spring-biased into 4 said groove freely to support said spring within said cavity, and means forming a driving connection between said spring and said cap whereby said spring by rotation of said cap may be wound about and in tightly gripping relation with bared conductors inserted therein, said groove forming the sole support of said spring adjacent said open end thereby to increase the springgripping action on bared conductors upon application of withdrawal forces on said cap, said forces acting through said groove to compress said spring around and about conductors inserted therein to increase the gripping engagement therewith and to prevent withdrawal of said cap from the conductors. 2. The wire connector of claim 1 in which said means forming said driving connection comprises an outwardly turned end on said coil of maximum dimension disposed Within a recess of said cap.

654,131 France Nov. 20, 1928 Great Britain Sept. 15, 1932 

1. AN ELECTRICAL WIRE CONNECTOR FOR BARED ENDS OF INSULATED CONDUCTORS COMPRISING AN INSULATING CAP HAVING A CENTRAL LONGITUDINAL CAVITY THEREIN OPEN AT THE FORWARD END AND CLOSED AT THE REAR END WITH A GROOVE ADJACENT SAID OPEN END. A FREE-FLOATING SPRING OF GENERALLY CONICAL SHAPE WITH THE TURNS UNIFORMLY SPACED ONE FROM THE OTHER AND WITH ITS TURN OF MAXIMUM DIAMETER SPRIN-BASED INTO SAID GROOVE FREELY TO SUPPORT SAID SPRING WITHIN SAID CAVITY, AND MEANS FORMING A DRIVING CONNECTION BETWEEN SAID SPRING AND SAID CAP WHEREBY SAID SPRING BY ROTATION OF SAID CAP MNAY BE WOUND ABOUT AND IN TIGHTLY GRIPPING RELATION WITH BARED CONDUCTORS INSERTED THEREIN. SAID GROOVE FORMING THE SOLD SUPPORT OF SAID SPRING ADJACENT SAID OPEN END THERRBY TO INCREASE THE SPRINGGRIPPING ACTION ON BARED CONDUCTORS UPON APPLICATION OF WITHDRAWAL FORCES ON SAID CAP, SAID FORCES ACTING THROUGH SAID GROOVE TO COMPRESS SAID SPRING AROUND AND ABOUT CONDUCTORS INSERTED THEREIN TO INCREASE THE GRIPPING ENGAGEMENT THEREWITH AND TO PREWVENT WITTHDRAWAL OF SAID CAP FROM THE CONDUCTORS. 